Injection molding assemblies are known to include a variety of components including an injection molding machine and a mold. An injection molding machine can be capable of receiving injection molding material, heating the material, and forcing the injection molding material into the mold.
A mold can comprise a number of components. In one embodiment a mold can comprise a stationary section and a moveable section, a hot runner comprising a channel assembly having one or more channels, heating elements for heating the one or more channel and a system of nozzles, and a cavity releasably closable in relation to the stationary section. Where a mold comprises a hot runner, the stationary section is sometimes referred to as a hot half and a moveable section is sometimes referred to as a cold half. Some hot runners are equipped with a temperature regulator for regulating a temperature of injection molding material (a melt stream) through a hot runner. A temperature regulator can include temperature sensors operatively disposed to sense a temperature of a hot runner. Other injection molding systems without hot runners have unheated channels through which injection molding material flows.
In the performance of a production run, an injection molding assembly including a certain mold is typically operated to perform typically a number of cycles. For each cycle, the cold half of the mold can be clamped to the hot half of the mold, subject to injection of injection molding material into the cavity, allowed to harden, and then de-clamped to release an injection molding product. U.S. Patent Publication No. 2004/0247724 describes a contact sensing sensor unit for use in counting a number of openings and closings of moveable and stationery mold sections. The contact sensing sensor unit of U.S. Patent Publication No. 2004/0247724 is disposed at an external surface of a stationary mold section.